ISSN:
0899-0042
Keywords:
nucleophilic aromatic substitution
;
optical resolution
;
asymmetric synthesis
;
diastereoselective reaction
;
Grignard reaction
;
atrolactic acid derivatives
;
biaryl coupling reaction
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Novel 1-aryl-9H-fluoren-9-ols 1 were conveniently synthesized by using the ester-mediated nucleophilic aromatic substitution on 2,6-dimethoxybenzoate 2 by aryl Grignard reagents as the key step. Racemic 1-phenylfluorenol 1a was converted to the diastereomeric esters 8 of (S)-2′-methoxy-1,1′-binaphthyl-2-carboxylic acid, which were readily separable by silica-gel column chromatography. Reduction of the optically pure diastereomer (+)-8 with LiAlH4 accompanied an appreciable racemization to give (+)-1a of 89% ee, which provides the first isolation of an optically active fluorenol of defined enantiomeric purity. Intrinsic chiral induction abilities of the 9-fluorenols 1 were examined in the atrolactic acid synthesis from phenylglyoxylates 9 and methylmagnesium iodide with diastereoselectivity of up to 85% de and the binaphthyl coupling of 1-methoxy-2-naphthoates 11 with 2-methoxy-1-naphthylmagnesium bromide with up to 73% de. Chirality 10:619-626, 1998. © 1998 Wiley-Liss, Inc.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
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